installing new piston should I do anything else?

25 replies to this topic
  • KJK_JR

Posted December 27, 2011 - 08:48 PM


For one thing, that's not the cylinder. Minor scoring in the lifter bores is not necessarily something bad enough to warrant replacement of the head. If the lifter fits well, has acceptable clearance, and moves freely in the bore, it's serviceable. You may want to knock down any high spots with some fine sand paper (but CLEAN it up if you do), but that doesn't look like a deal breaker to me.

I'm aware it's not the cylinder which is why i said "cylinder head" the cylinder itself is a different story. But what would be the reason for the wear on the valve lifters and the area around them?

  • grayracer513

Posted December 27, 2011 - 11:11 PM


According to the manual if these scratches exist it says to replace the cylinder.

Just going by how it was written. :bonk:

Scoring of the lifter bores is virtually always due to dirt or engine debris getting in there.

  • KJK_JR

Posted December 28, 2011 - 06:36 AM


Just going by how it was written. :bonk:

Scoring of the lifter bores is virtually always due to dirt or engine debris getting in there.

:smirk: Sorry didn't catch that one.

But then wouldn't my cams have some sort of wear?

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  • grayracer513

Posted December 28, 2011 - 06:52 AM


Not necessarily.

  • rickallen124

Posted December 30, 2011 - 07:53 AM


Aside from the carbon build-up on the valves, they dont look too bad. Clean them up good and post new pics.

Try runnung come Chevron Techron concentrate or BG 44K on a regular basis and you shouldn't have any carbon build up.

What ratio would you run the Chevron Techron concentrate at? I have the bottles that are designed for dumping in a car at fill up, so half a bottle for 5 gallons?

  • grayracer513

Posted December 30, 2011 - 08:18 AM


The average car is ~15 gallons, so....

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